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Number of results: 90
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Abstract

In this paper an artificial neural network, which realizes a nonlinear adaptive control algorithm, has been applied in a control system of variable speed generating system. The speed is adjusted automatically as a function of load power demand. The controller employs a single layer neural network to estimate the unknown plant nonlinearities online. Optimization of the controller is difficult because the plant is nonlinear and no stationary. Furthermore, it deals with the situation where the plant becomes uncontrollable without any restrictive assumptions. In contrast to previous work [1] on the same subject, the number of neural networks has been reduced to only one network. The number of the neurons in a network structure as well as choosing certain design parameters was specified a priori. The computer test results have been presented to show performance of proposed neural controller.

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Authors and Affiliations

L.M. Grzesiak
J. Sobolewski
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Abstract

The paper contains a short literature review on the subject of special type of thin film structures with resistiveswitching memory effect. In the literature, such structures are commonly labeled as "memristors". The word "memristor" originates from two words: "memory" and "resistor". For the first time, the memristor was theoretically described in 1971 by Leon Chua as the 4th fundamental passive electronics element with a non-linear current-voltage behavior. The reported area of potential usage of memristor is enormous. It is predicted that the memristor could find application, for example in the domain of nonvolatile random access memory, flash memory, neuromorphic systems and so forth. However, in spite of the fact that plenty of papers have been published in the subject literature to date, the memristor still behaves as a "mysterious" electronic element. It seems that, one of the important reasons that such structures are not yet in practical use, is unsufficient knowledge of physical phenomena determining occurrence of the switching effect. The present paper contains a literature review of available descriptions of theoretical basis of the memristor structures, used materials, structure configurations and discussion about future prospects and limitations.

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Authors and Affiliations

Jarosław Domaradzki
Damian Wojcieszak
Tomasz Kotwica
Ewa Mańkowska
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Abstract

Permanent magnet motors are more and more frequently used in various applications. In this group motors with a trapezoidal EMF deserve a special attention. They are characterized by a simple construction, high efficiency and high torque overload. A certain drawback of BLDC motors are difficulties with an operation at a speed above the nominal value. The article presents the results of investigations into the variablestructure electronic commutator designed for the drive of a small electric vehicle equipped with BLDC motors. Such a solution allows extending the standard range of the drive's speed. The considerations contained in the article focus on the possibilities and effects of regeneration mode in the proposed topology of converter. A theoretical analysis has been presented as well as computer simulations carried out by means of Matlab- Simulink, which were then verified at a laboratory. The tests were finished with trias conducted using a small electric vehicle Elipsa.

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Authors and Affiliations

Tomasz Biskup
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Abstract

The paper presents the method of control of an induction squirrel-cage machine supplied by a voltage source converter. The presented idea is based on an innovative method of the voltage source converter control, consisting in direct joining of the motor control system with the voltage source rectifier control system. The combined control system gives good dc-bus voltage stabilization. In the applied control system the limits of the reference variables have been introduced. A correction of the estimated machine load torque is proposed. The new proposed solutions are confirmed by mathematical dependences, simulation and experimental results.

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Authors and Affiliations

Marcin Morawiec
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Abstract

This paper presents an experimental system for remote communication between road users and traffic signs. Implemented solution consists of two modules: a transmitter (traffic sign), including novel system for remote waking-up by the passing vehicle with use of the quasi-passive (biased) diode detector circuit, and a receiver (vehicle), which is responsible for wake-up signaling and interpreting received messages. Both modules use Wi-Fi protocol operating in 2.4 GHz ISM band for sending data, and OOK signaling in 868 MHZ ISM band for sending wake-up signals. The paper provides theoretical analysis, description of design challenges and chosen solutions, and finally, laboratory measurements as well as the results of tests conducted in the systems’ target environment with a moving vehicle, confirming correct operation of the system.
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Authors and Affiliations

Konrad Janisz
Jacek Stępień
Szczepan Odrobina
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Abstract

Most of the developing countries economy largely depends on the agriculture. More than half of the population rely on agriculture related activities for their survival. In spite of dependency on agriculture, the technological development of agricultural work in developing country is not comparable to the countries like Australia or Israel. The main reason behind the lack of development is the small size of farms. Such farmers cannot afford expensive technology available in the market due to limited profit margins. The report describes an autonomous fertilization system that takes care of the fertilization requirements of the small scale farms at affordable rates. The system is divided in two parts namely User Interface and Control System. The user interface is designed using the state of the art Raspberry Pi board and a touch screen LCD. The control system is developed using the Arduino platform and can control five fertilizers at a time. The output of the system is the mix of the fertilizer, which is forced into the drip irrigation system of the farm. The system has built in data for the fertilization requirement for important crops and vegetation. The system also facilitates the customize fertilization requirements to be added in the system as per the user requirements.

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Authors and Affiliations

Vijay Savani
Akash Mecwan
Jayesh Patel
Piyush Bhatasana
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Abstract

Temperature change is one of key factors which should be taken into account in logistics during transportation or storage of many types of goods. In this study, a passive UHF RFID-enabled sensor system for elevated temperature (above 58°C) detection has been demonstrated. This system consists of an RFID reader and disposable temperature sensor comprising an UHF antenna, chip and temperature sensitive unit. The UHF antenna was designed and simulated in an IE3D software. The properties of the system were examined depending on the temperature level, type of package which contains the studied objects and the type of antenna substrate.

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Authors and Affiliations

Kamil Janeczek
Małgorzata Jakubowska
Grażyna Kozioł
Piotr Jankowski-Mihułowicz
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Abstract

The Low Temperature Joining Technique (LTJT) using silver compounds enables to significantly increase the thermal conductivity between joined elements, which is much higher than for soldered joints. However, it also makes difficult to measure the thermal conductivity of the joint. The Laser Flash Analysis (LFA) is a non-intrusive method of measuring the temperature rise of one surface of a specimen after excitation with a laser pulse of its other surface. The main limitation of the LFA method is its standard computer software, which assumes the dimensions of a bonded component to be similar to those of the substrate, because it uses the standard Parker’s formula dedicated for one-dimensional heat flow. In the paper a special design of measured specimen was proposed, consisting of two copper plates of different size joined with the sintered silver layer. It was shown that heat properties of these specimens can also be measured after modifying the LFA method. The authors adapted these specimens by masking the false heat signal sourced from the uncovered plate area. Another adaptation was introducing a correcting factor of the heat travel distance, which was calculated with heat-flow simulations and placed into the Parker’s formula. The heat-flow simulated data were compared with the real LFA measurement results, which enabled estimation of the joint properties, e.g. its porosity.
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Authors and Affiliations

Jerzy Szałapak
Konrad Kiełbasiński
Jakub Krzemiński
Anna Młożniak
Elżbieta Zwierkowska
Małgorzata Jakubowska
Radosław Pawłowski
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Abstract

The article presents the analysis of the simulation test results for three variants of the power electronics used as interface between the power network and superconducting magnetic energy storage (SMES) with the following parameters: power of 250 kW, current of 500 A DC and voltage of 500 V DC. Three interface topologies were analyzed: two-level AC-DC and DC-DC converters; three-level systems and mixed systems combining a three-level active rectifier and a two-level DC-DC converter. The following criteria were considered: input and output current and voltage distortions, determined as THDi and THDu, power losses in power electronics components; cost of the semiconductor components for each topology and total cost of the interface. Results of the analysis showed that for high-power low-voltage and high-current power electronics systems, the most advantageous solution from a technical and economical perspective is a two-level interface configuration in relation to both AC-DC and DC-DC converters.

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Authors and Affiliations

A. Domino
K. Zymmer
M. Parchomiuk
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Abstract

The concept of control over electronic transferable records is the central premise of the UNCITRAL Model Law on Transferable Electronic Records. It indicates the method of determining the party who has the rights embodied in the negotiable electronic record. The purpose of this article is to present the most important issues related to documents and instruments that have a circular function in international maritime trade, and the intention to create a legal framework for them when they take the form of electronic records.

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Authors and Affiliations

Maria Dragun-Gertner
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Abstract

Ongoing energy measurement is one of the parameters such as: electron beam current, transporter speed, or scanning width, that must be recorded according to the conditions imposed in the accelerator validation procedure. Described measurement method based on the use of a secondary electron collecting electrode has been tested at the electron beam linear accelerator installation typically used for radiation sterilization. Data processing and presentation of the electron beam characteristics is based on the information obtained via dedicated pulse acquisition interface. The energy spectra parameters provide data for modeling and calculation of dose distribution for irradiation process optimization and also knowledge of accelerator RF alignment in case of service.
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Authors and Affiliations

S. Bułka
1
Z. Zimek
1

  1. Institute of Nuclear Chemistry and Technology, Centre of Radiation Chemistry Research and Technology, Warsaw, Poland
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Abstract

Scanning electron microscopy (SEM) is a perfect technique for micro-/nano-object imaging [1] and movement measurement [2, 3] both in high and environmental vacuum conditions and at various temperatures ranging from elevated to low temperatures. In our view, the magnetic field expanding from the pole-piece makes it possible to characterize the behaviour of electromagnetic micro- and nano electromechanical systems (MEMS/NEMS) in which the deflection of the movable part is controlled by the electromagnetic force. What must be determined, however, is the magnetic field expanding from the e-beam column, which is a function of many factors, like working distance (WD), magnification and position of the device in relation to the e-beam column. There are only a few experimental methods for determination of the magnetic field in a scanning electron microscope. In this paper we present a method of the magnetic field determination under the scanning electron column by application of a silicon cantilever magnetometer. The micro-cantilever magnetometer is a silicon micro-fabricated MEMS electromagnetic device integrating a current loop of lithographically defined dimensions. Its stiffness can be calibrated with a precision of 5% by the method described by Majstrzyk et al. [4]. The deflection of the magnetometer cantilever is measured with a scanning electron microscope and thus, through knowing the bias current, it is possible to determine the magnetic field generated by the e-beam column in a defined position and at a defined magnification.

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Authors and Affiliations

Karolina Orłowska
Maria E. Mognaschi
Krzysztof Kwoka
Tomasz Piasecki
Piotr Kunicki
Andrzej Sierakowski
Wojciech Majstrzyk
Arkadiusz Podgórni
Bartosz Pruchnik
Paolo di Barba
Teodor Gotszalk
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Abstract

Fault detection and location are important and front-end tasks in assuring the reliability of power electronic circuits. In essence, both tasks can be considered as the classification problem. This paper presents a fast fault classification method for power electronic circuits by using the support vector machine (SVM) as a classifier and the wavelet transform as a feature extraction technique. Using one-against-rest SVM and one-against-one SVM are two general approaches to fault classification in power electronic circuits. However, these methods have a high computational complexity, therefore in this design we employ a directed acyclic graph (DAG) SVM to implement the fault classification. The DAG SVM is close to the one-against-one SVM regarding its classification performance, but it is much faster. Moreover, in the presented approach, the DAG SVM is improved by introducing the method of Knearest neighbours to reduce some computations, so that the classification time can be further reduced. A rectifier and an inverter are demonstrated to prove effectiveness of the presented design.

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Authors and Affiliations

Jiang Cui
Ge Shi
Chunying Gong
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Abstract

A simple analog circuit is presented which can play a neuron role in static-model-based neural networks implemented in the form of an integrated circuit. Operating in a transresistance mode it is suited to cooperate with transconductance synapses. As a result, its input signal is a current which is a sum of currents coming from the synapses. Summation of the currents is realized in a node at the neuron input. The circuit has two outputs and provides a step function signal at one output and a linear function one at the other. Activation threshold of the step output can be conveniently controlled by means of a voltage. Having two outputs, the neuron is attractive to be used in networks taking advantage of fuzzy logic. It is built of only five MOS transistors, can operate with very low supply voltages, consumes a very low power when processing the input signals, and no power in the absence of input signals. Simulation as well as experimental results are shown to be in a good agreement with theoretical predictions. The presented results concern a 0.35 1m CMOS process and a prototype fabricated in the framework of Europractice.

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Authors and Affiliations

R. Wojtyna
T. Talaśka
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Abstract

The implementation of milk-run in Indonesia has been started since 2005. As a developing

country, there is a challenge to operate milk-run smoothly especially in urban area due to

severe traffic congestion and unfavourable road condition in some areas. This research aimed

to analyze the practice of milk-run operation in one of the biggest Japanese automotive

companies in Indonesia. Transportation Value Stream Mapping (TVSM) is applied in order

to perform just-in-time delivery in the supply chain before operating milk-run. It is discussed

that this company still need to continue in improving milk-run operation. The operation

system needs control and integration from manufacturer, supplier and logistics partner.

The advantage of milk-run operation is cost reduction and also support green logistics in

decreasing emission of carbondioxide (CO2) by reducing the number of trucks used.

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Authors and Affiliations

Humiras Hardi Purba
Adi Fitra
Aina Nindiani
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Abstract

The aim of this work was to evaluate the use of the naphthalic anhydride safener on the protection of common bean cultivars BRS-Estilo (carioca) and BRS-Esplendor (black) from negative effects of herbicides. Two experiments were conducted, one for each cultivar in a complete randomized design with five replications, in a 6 × 3 factorial scheme, with six herbicide treatments: bentazon, fluazifop-P + fomesafen, bentazon + imazamox, fomesafen, cloransulam, and control without application, and three naphthalic anhydride treatments: without application, foliar application, and application via seed treatment. Visible injuries at 7, 14 and 21 days after application, photosystem II electron transport rate, and plant dry weight were evaluated. The naphthalic anhydride applied via foliar, and seed treatment reduced significantly the visible injuries in relation to the control when using the herbicides bentazon, fluazifop-P + fomesafen, bentazon + imazamox, and cloransulam. The photosystem II electron transport rate was protected by anhydride applied via foliar and seed treatment when using the herbicides bentazon, fluazifop-P + fomesafen and bentazon + + imazamox. The application of naphthalic anhydride via seed treatment protected the BRS-Estilo and BRS-Esplendor common bean cultivars, with no reductions in the plant dry weight when using the herbicides fluazifop-P + fomesafen, and fomesafen. The use of naphthalic anhydride via seed treatment and foliar application protected BRS-Estilo and BRSEsplendor common bean cultivars, from the negative effects of fluazifop-P + fomesafen and fomesafen herbicides. Thus, this practice has potential to be used in common beans.

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Authors and Affiliations

Fábio Henrique Krenchinski
Edicarlos Batista de Castro
Victor José Salomão Cesco
Diego Belapart
Danilo Morilha Rodrigues
Caio Antonio Carbonari
Edivaldo Domingues Velini
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Abstract

In this work we report on fabrication of quantum wires and quantum point contacts from the modulation doped CdMgTe/Cd(Mn)Te structures, with the application of a high-resolution electron-beam lithography. We emphasize on methods which were not yet utilized for these substrate materials. In particular, we describe the so-called shallow-etching approach, which allows for the fabrication of quantum constrictions of a physical width down to 100 nm, which are characterized by the smoother confining potential as compared to the deep-etched devices. For that purpose, a single-line exposure mode of electron-beam lithography has been used. We demonstrate also, how to combine the etching of separating grooves with the thermal evaporation of metal side-gates into a single post-processing stage of a quantum point contact fabrication.

This article is an expanded version of the scientific reports presented at the International Conference on Semiconductor Nanostructures for Optoelectronics and Biosensors 2016 ICSeNOB2016, May 22–25, 2016, Rzeszow, Poland.

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Authors and Affiliations

Joanna Wróbel
E. Bobko
Dariusz Płoch
ORCID: ORCID
M. Wiater
T. Wojtowicz
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Abstract

The paper presents a new second-cycle Electronics and Telecommunications study program that has been running in Lodz University of Technology since 2020. The concept of the program uses the Project Based Learning approach and it is based on three main projects implemented throughout the curriculum. The inspiration was the programs of three foreign universities and extensive research of various groups of stakeholders. The initial evaluation of the program first semester proves high acceptance and satisfaction of the students.
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Authors and Affiliations

Ewa Raj
1
Krzysztof Tomalczyk
2

  1. Department of Semiconductor and Optoelectronic Devices, Lodz University of Technology, Poland
  2. Institute of Electronics, Lodz University of Technology, Poland
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Abstract

Metal-intermetallic layered (MIL) composites attract considerable attention due to their remarkable structural and ballistic performance. This study aimed to develop a Ti/Al-based multilayered MIL material by adding ceramic powders, since they can improve the composite’s impact resistance. To this end, an experiment was conducted which a stack of alternating Ti and Al sheets bonded by hot pressing; Ti/Al multilayers containing additional layers of Al2O3 and SiC powders were also produced. The samples obtained were examined using electron microscopy techniques. The clads’ mechanical properties were investigated using a Charpy hammer. In the reaction zone, only one intermetallic phase occurred: the Al3Ti phase. The model with an additional Al2O3 layer showed the highest impact energy. None of the Ti/Al clads broke during the Charpy impact test, a result proving their high ductility.
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Bibliography

[1] I.A. Bataev, A.A. Bataev, V.I. Mali, D.V. Pavliukova, Structural and mechanical properties of metallic-intermetallic laminate composites produced by explosive welding and annealing, Mater. Design 35, 225-234 (2012). DOI: https://doi.org/10.1016/j.matdes.2011.09.030
[2] F. Foadian, M. Soltanieh, M. Adeli, M. Etminanbakhsh, A Study on the Formation of Intermetallics During the Heat Treatment of Explosively Welded Al-Ti Mulitlayers, Metall. Mater. Trans. A 45A, 1823 (2014). DOI: https://doi.org/10.1007/s11661-013-2144-6
[3] H. Paul, Ł. Maj, M. Prażmowski, A. Gałka, M. Miszczyk, P. Petrzak, Microstructure and mechanical properties of multilayered Al/Ti composites produced by explosive welding, Procedia Manufacturing 15, 1391-1398 (2018). DOI: https://doi.org/10.1016/j.promfg.2018.07.343
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Authors and Affiliations

W. Kowalski
1
ORCID: ORCID
H. Paul
1
ORCID: ORCID
P. Petrzak
1
ORCID: ORCID
Ł. Maj
1
ORCID: ORCID
I. Mania
1
ORCID: ORCID
M. Faryna
1
ORCID: ORCID

  1. Institute of Metallurgy and Materials Science , Polish Academy of Sciences , 25 Reymonta Str., 30-059 Kraków, Poland
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Abstract

In this study, we have developed Sn-Ag alloy by a simple high energy ball milling technique. We have ball-milled the eutectic mixture of Sn and Ag powders for a period of 45 h. The milled powder for 45 h was characterized for particle size and morphology. Microstructural investigations were carried out by scanning electron microscopy and X-ray diffraction studies. The melting behavior of 45 h milled powder was studied by differential scanning calorimetry. The resultant crystallite size of the Sn(Ag) solid solution was found to be 85 nm. The melting point of the powder was 213.6oC after 45 h of milling showing depression of ≈6oC in melting point as compared to the existing Sn-3.5Ag alloys. It was also reported that the wettability of the Sn-3.5Ag powder was significantly improved with an increase in milling time up to 45 h due to the nanocrystalline structure of the milled powder.

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Authors and Affiliations

Ashutosh Sharma
ORCID: ORCID
Byungmin Ahn
ORCID: ORCID
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Abstract

The paper presents the effect of electron beam alloying on the surface of a copper flat bar (M1Ez4) with titanium powder. Due to the quality of the surface after alloying and the obtained properties, the parameters used were given which met the assumed conditions to the greatest extent. The microstructure and mechanical properties as well as the chemical composition of surface-modified electron-beam copper show improved mechanical properties, i.e. hardness and abrasion resistance. This article uses research techniques using scanning electron microscopy and analysis of chemical composition in micro-areas (EDS). In order to examine the properties of the material after electron beam modification, hardness measurements were performed at low loads (HV0.1), abrasion resistance was tested, and conductivity was also measured. As a result of modifying the chemical and phase composition of M1E copper using an electron beam, the hardness increased by 46%, while the conductivity decreased by 16% due to the formation of intermetallic phases during solidification.
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Bibliography

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[3] Guo, S., Zhou, Q., Kong, J., Peng, Y., Xiang, Y., Luo, T., Wang, K. & Zhu, J. (2016). Effect of beam offset on the characteristics of copper/304stainless steel electron beam welding. Vacuum. 128, 205-212. DOI: 10.1016/j.vacuum.2016.03.034.
[4] Zhan, X., Yu, H., Feng, X., Pan, P. & Liu, Z. (2019). A comparative study on laser beam and electron beam welding of 5A06 aluminum alloy. Materials Research Express. 6(5), 056563. DOI: 10.1088/2053-1591/ab0562.
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[6] Pakieła, W. & Brytan, Z. (2020). Laser surface alloying of aluminum alloys with Cu/Fe metallic powders. Solid State Phenomena. 308, 64-75, DOI: 10.4028/www.scientific.net/SSP.308.64.
[7] Pakieła, W., Tański, T., Brytan, Z., Chladek, G. & Pakieła, K. (2020). The impact of laser surface treatment on the microstructure, wear resistance and hardness of the AlMg5 aluminum alloy. Applied Physics A. 126, 1-10. DOI: 10.1007/s00339-020-3350-x.
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[13] Patidar, D. & Rana, R.S. (2018). The effect of CO2 laser cutting parameter on Mechanical & Microstructural characteristics of high strength steel-a review. Materials Today: Proceedings. 5(9), Part 3, 17753-17762. DOI: 10.1016/j.matpr.2018.06.099.
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[19] Ran, Q., Liu, J., Wang, X. & Liu, J. (2021). The Effect of Heat Treatment on the Microstructure Evolution and Properties of an Age-Hardened Cu-3Ti-2Mg Alloy. Archives of Metallurgy and Materials. 66(1), 163-170. DOI: 10.24425/amm.2021.134772. https://journals.pan.pl/dlibra/publication/134772/edition/117801
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Authors and Affiliations

P.E. Smolarczyk
1
ORCID: ORCID
M. Krupiński
1
ORCID: ORCID
M. Węglowski
2
ORCID: ORCID
Wojciech Pakieła
1
ORCID: ORCID
P. Śliwiński
2
ORCID: ORCID

  1. Department of Engineering Materials and Biomaterials, Silesian University of Technology, Konarskiego 18A, 44-100 Gliwice, Poland
  2. Łukasiewicz Research Network – Upper Silesian Institute of Technology, Bł. Czesława 16-18, 44-100 Gliwice, Poland
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Abstract

The electron field and photo-field emission from GaN nanostructures has been analyzed in this review. In order to explain the obtained experimental results, a model was proposed taking into account the change in carrier concentration distribution in the main and the satellite valley during the emission process. The lowering of work function (due to the increased number of carriers in the satellite valley) can explain the decrease in the Fowler-Nordheim plot slope. It was shown that the energy difference between the main and satellite valley in GaN was decreased in the case of quantum confinement, thus increasing the probability of electron transition from Γ to X valley at same electric fields.

Investigations of electron photo-field emission demonstrated that the Fowler–Nordheim plots of the emission current have different slopes for nonilluminated and illuminated devices. A model based on the electron emission from valleys having different specific electron affinities is proposed to explain the experimental results. In the absence of illumination the emission takes place only from the lower valley. Upon UV illumination and presence of a high electric field at the emitter tip, the upper valley of the conduction band appears to be occupied by electrons generated at the valence band.

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Authors and Affiliations

V. Litovchenko
A. Evtukh
A. Grygoriev
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Abstract

A methodology is proposed for modifying computer ontologies (CO) for electronic courses (EC) in the field of information and communication technologies (ICT) for universities, schools, extracurricular institutions, as well as for the professional retraining of specialists. The methodology includes the modification of CO by representing the formal ontograph of CO in the form of a graph and using techniques for working with the graph to find optimal paths on the graph using applied software (SW). A genetic algorithm (GA) is involved in the search for the optimal CO. This will lead to the division of the ontograph into branches and the ability to calculate the best trajectory in a certain sense through the EC educational material, taking into account the syllabus. An example is considered for the ICT course syllabus in terms of a specific topic covering the design and use of databases. It is concluded that for the full implementation of this methodology, a tool is needed that automates this procedure for developing EC and/or electronic textbooks. An algorithm and a prototype of software tools are also proposed, integrating machine methods of working with CO and graphs.
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Authors and Affiliations

Nazym Sabitova
1
Yuriy Tikhonov
2
Valerii Lakhno
3
Makulov Kariyrbek
4
Olena Kryvoruchko
5
Vitalyi Chubaievskyi
5
Alona Desiatko
5
Mereke Zhumadilova
4

  1. Eurasian National University, Astana, Kazakhstan
  2. Luhansk Taras Shevchenko National University, Poltava, Ukraine
  3. National University of Life and Environmental Sciences of Ukraine, Kyiv, Ukraine
  4. Yessenov University, Aktau, Kazakhstan
  5. State University of Trade and Economics, Kyiv, Ukraine

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